The aim of this project is to produce monoclonal antibodies against various components of the T cell receptor-T3 complex in mouse. These reagents will be used to study the assembly of the complex during development, to investigate differences in the structure of T3 on mouse alpha beta- or gamma delta-bearing cells, in blocking experiments to establish the physical relationships between different components of the complex and as probes for the analysis of the T cell repertoire in different mouse strains and different responses. They will be used by other projects in this program. It is also expected that like the other antibodies of this types that we and others have produced, the new monoclonal anti-T3 cell receptor and anti-T3 antibodies will have multiple uses by the many other investigators in this field to whom they will be given freely. We plan to produce monoclonal antibodies against murine V alphas (specifically V alpha11 and V alpha5) and V betas (specifically V beta3 and V beta5), against T cell receptor constant region determinants and against T3 proteins.